====================================================== kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env WARNING: possible circular locking dependency detected 4.14.143 #0 Not tainted ------------------------------------------------------ syz-executor.1/586 is trying to acquire lock: ((&strp->work)){+.+.}, at: [] flush_work+0x84/0x730 kernel/workqueue.c:2878 but task is already holding lock: (sk_lock-AF_INET){+.+.}, at: [] lock_sock include/net/sock.h:1462 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_attach net/kcm/kcmsock.c:1390 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x35d/0x1120 net/kcm/kcmsock.c:1701 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_INET){+.+.}: lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991 lock_sock_nested+0xbd/0x110 net/core/sock.c:2765 lock_sock include/net/sock.h:1462 [inline] strp_sock_lock+0x2e/0x40 net/strparser/strparser.c:451 do_strp_work net/strparser/strparser.c:415 [inline] strp_work+0x43/0x100 net/strparser/strparser.c:434 process_one_work+0x863/0x1600 kernel/workqueue.c:2114 worker_thread+0x5d9/0x1050 kernel/workqueue.c:2248 kthread+0x319/0x430 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 -> #0 kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' ((&strp->work)){+.+.}: check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991 flush_work+0xae/0x730 kernel/workqueue.c:2881 __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 strp_done+0x58/0xe0 net/strparser/strparser.c:519 kcm_attach net/kcm/kcmsock.c:1429 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] kcm_ioctl+0x8d9/0x1120 net/kcm/kcmsock.c:1701 kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env sock_do_ioctl+0x64/0xb0 net/socket.c:974 sock_ioctl+0x2a6/0x470 net/socket.c:1071 kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET); lock((&strp->work)); lock(sk_lock-AF_INET); lock((&strp->work)); *** DEADLOCK *** 1 lock held by syz-executor.1/586: #0: (sk_lock-AF_INET){+.+.}, at: [] lock_sock include/net/sock.h:1462 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_attach net/kcm/kcmsock.c:1390 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x35d/0x1120 net/kcm/kcmsock.c:1701 stack backtrace: CPU: 0 PID: 586 Comm: syz-executor.1 Not tainted 4.14.143 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x197 lib/dump_stack.c:53 print_circular_bug.isra.0.cold+0x1cc/0x28f kernel/locking/lockdep.c:1258 kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' check_prev_add kernel/locking/lockdep.c:1901 [inline] check_prevs_add kernel/locking/lockdep.c:2018 [inline] validate_chain kernel/locking/lockdep.c:2460 [inline] __lock_acquire+0x2cb3/0x4620 kernel/locking/lockdep.c:3487 lock_acquire+0x16f/0x430 kernel/locking/lockdep.c:3991 kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env flush_work+0xae/0x730 kernel/workqueue.c:2881 kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' __cancel_work_timer+0x2f0/0x480 kernel/workqueue.c:2956 cancel_work_sync+0x18/0x20 kernel/workqueue.c:2992 strp_done+0x58/0xe0 net/strparser/strparser.c:519 kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kcm_attach net/kcm/kcmsock.c:1429 [inline] kcm_attach_ioctl net/kcm/kcmsock.c:1490 [inline] kcm_ioctl+0x8d9/0x1120 net/kcm/kcmsock.c:1701 sock_do_ioctl+0x64/0xb0 net/socket.c:974 kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' sock_ioctl+0x2a6/0x470 net/socket.c:1071 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4598e9 RSP: 002b:00007fd988047c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004598e9 RDX: 0000000020000140 RSI: 00000000000089e0 RDI: 0000000000000005 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd9880486d4 R13: 00000000004c5846 R14: 00000000004d9fa8 R15: 00000000ffffffff kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'loop1' (ffff8880a49b0ee0): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop1' (ffff8880a49b0ee0): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop0' (ffff88805f47a560): kobject_uevent_env kobject: 'loop0' (ffff88805f47a560): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop3' (ffff8880a4a4d1e0): kobject_uevent_env kobject: 'loop3' (ffff8880a4a4d1e0): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'loop2' (ffff8880a4a0f7e0): kobject_uevent_env kobject: 'loop2' (ffff8880a4a0f7e0): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop0' (ffff88805f47a560): kobject_uevent_env kobject: 'loop0' (ffff88805f47a560): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'input5' (ffff8880647e2fa0): kobject_add_internal: parent: 'input', set: 'devices' kobject: 'input5' (ffff8880647e2fa0): kobject_uevent_env kobject: 'input5' (ffff8880647e2fa0): fill_kobj_path: path = '/devices/virtual/input/input5' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'input5' (ffff8880647e2fa0): fill_kobj_path: path = '/devices/virtual/input/input5' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' input: syz1 as /devices/virtual/input/input5 kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'event4' (ffff888081538a78): kobject_add_internal: parent: 'input5', set: 'devices' kobject: 'event4' (ffff888081538a78): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'event4' (ffff888081538a78): fill_kobj_path: path = '/devices/virtual/input/input5/event4' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'event4' (ffff888081538a78): kobject_uevent_env kobject: 'event4' (ffff888081538a78): fill_kobj_path: path = '/devices/virtual/input/input5/event4' kobject: '(null)' (ffff888081538ea8): kobject_cleanup, parent ffff888081538a78 kobject: '(null)' (ffff888081538ea8): calling ktype release kobject: 'event4' (ffff888081538a78): kobject_cleanup, parent (null) kobject: 'event4' (ffff888081538a78): calling ktype release kobject: 'event4': free name kobject: 'input5' (ffff8880647e2fa0): kobject_uevent_env kobject: 'input5' (ffff8880647e2fa0): fill_kobj_path: path = '/devices/virtual/input/input5' kobject: 'input5' (ffff8880647e2fa0): kobject_cleanup, parent (null) kobject: 'input5' (ffff8880647e2fa0): calling ktype release kobject: 'input5': free name uinput: write device info first kobject: 'input6' (ffff8880699d7960): kobject_cleanup, parent (null) kobject: 'input6' (ffff8880699d7960): calling ktype release kobject: 'input6': free name kobject: 'loop0' (ffff88805f47a560): kobject_uevent_env kobject: 'loop0' (ffff88805f47a560): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (ffff8880a49b0ee0): kobject_uevent_env kobject: 'loop1' (ffff8880a49b0ee0): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop3' (ffff8880a4a4d1e0): kobject_uevent_env kobject: 'loop3' (ffff8880a4a4d1e0): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop1' (ffff8880a49b0ee0): kobject_uevent_env kobject: 'loop1' (ffff8880a49b0ee0): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop2' (ffff8880a4a0f7e0): kobject_uevent_env 8021q: VLANs not supported on lo kobject: 'loop2' (ffff8880a4a0f7e0): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'input7' (ffff8880007119e0): kobject_add_internal: parent: 'input', set: 'devices' 8021q: VLANs not supported on lo kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'input7' (ffff8880007119e0): kobject_uevent_env kobject: 'input7' (ffff8880007119e0): fill_kobj_path: path = '/devices/virtual/input/input7' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'input7' (ffff8880007119e0): fill_kobj_path: path = '/devices/virtual/input/input7' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' input: syz1 as /devices/virtual/input/input7 kobject: 'event4' (ffff88808d7114b8): kobject_add_internal: parent: 'input7', set: 'devices' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'event4' (ffff88808d7114b8): kobject_uevent_env kobject: 'event4' (ffff88808d7114b8): fill_kobj_path: path = '/devices/virtual/input/input7/event4' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'event4' (ffff88808d7114b8): kobject_uevent_env kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'event4' (ffff88808d7114b8): fill_kobj_path: path = '/devices/virtual/input/input7/event4' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: '(null)' (ffff88808d7118e8): kobject_cleanup, parent ffff88808d7114b8 kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: '(null)' (ffff88808d7118e8): calling ktype release kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'event4' (ffff88808d7114b8): kobject_cleanup, parent (null) kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'event4' (ffff88808d7114b8): calling ktype release kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'event4': free name kobject: 'input7' (ffff8880007119e0): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'kvm' (ffff8880a7132890): kobject_uevent_env kobject: 'input7' (ffff8880007119e0): fill_kobj_path: path = '/devices/virtual/input/input7' kobject: 'input7' (ffff8880007119e0): kobject_cleanup, parent (null) kobject: 'kvm' (ffff8880a7132890): fill_kobj_path: path = '/devices/virtual/misc/kvm' kobject: 'input7' (ffff8880007119e0): calling ktype release kobject: 'input7': free name kobject: 'loop5' (ffff8880a4af6a20): kobject_uevent_env kobject: 'loop5' (ffff8880a4af6a20): fill_kobj_path: path = '/devices/virtual/block/loop5' kobject: 'loop0' (ffff88805f47a560): kobject_uevent_env kobject: 'loop0' (ffff88805f47a560): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (ffff8880a49b0ee0): kobject_uevent_env kobject: 'loop1' (ffff8880a49b0ee0): fill_kobj_path: path = '/devices/virtual/block/loop1' kobject: 'loop3' (ffff8880a4a4d1e0): kobject_uevent_env kobject: 'loop3' (ffff8880a4a4d1e0): fill_kobj_path: path = '/devices/virtual/block/loop3' kobject: 'loop2' (ffff8880a4a0f7e0): kobject_uevent_env kobject: 'loop2' (ffff8880a4a0f7e0): fill_kobj_path: path = '/devices/virtual/block/loop2' kobject: 'input8' (ffff8880974206a0): kobject_add_internal: parent: 'input', set: 'devices' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'input8' (ffff8880974206a0): kobject_uevent_env kobject: 'input8' (ffff8880974206a0): fill_kobj_path: path = '/devices/virtual/input/input8' kobject: 'input8' (ffff8880974206a0): fill_kobj_path: path = '/devices/virtual/input/input8' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' input: syz1 as /devices/virtual/input/input8 kobject: 'event4' (ffff8880a551cc78): kobject_add_internal: parent: 'input8', set: 'devices' kobject: 'event4' (ffff8880a551cc78): kobject_uevent_env kobject: 'event4' (ffff8880a551cc78): fill_kobj_path: path = '/devices/virtual/input/input8/event4' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'event4' (ffff8880a551cc78): kobject_uevent_env kobject: 'event4' (ffff8880a551cc78): fill_kobj_path: path = '/devices/virtual/input/input8/event4' kobject: '(null)' (ffff8880a551d0a8): kobject_cleanup, parent ffff8880a551cc78 kobject: 'loop4' (ffff8880a4a9c120): kobject_uevent_env kobject: '(null)' (ffff8880a551d0a8): calling ktype release kobject: 'loop4' (ffff8880a4a9c120): fill_kobj_path: path = '/devices/virtual/block/loop4' kobject: 'event4' (ffff8880a551cc78): kobject_cleanup, parent (null) kobject: 'event4' (ffff8880a551cc78): calling ktype release kobject: 'event4': free name kobject: 'input8' (ffff8880974206a0): kobject_uevent_env kobject: 'input8' (ffff8880974206a0): fill_kobj_path: path = '/devices/virtual/input/input8' kobject: 'input8' (ffff8880974206a0): kobject_cleanup, parent (null) kobject: 'input8' (ffff8880974206a0): calling ktype release kobject: 'input8': free name kobject: 'loop0' (ffff88805f47a560): kobject_uevent_env kobject: 'loop0' (ffff88805f47a560): fill_kobj_path: path = '/devices/virtual/block/loop0' kobject: 'loop1' (ffff8880a49b0ee0): kobject_uevent_env kobject: 'loop1' (ffff8880a49b0ee0): fill_kobj_path: path = '/devices/virtual/block/loop1'